The present invention relates to a cylindrical mounting having a clearance-free fit, in particular, for a photographic lens. The mounting comprises a main mounting and at least one individual mounting which can be assembled therein by means of a frictional connection of the inner and outer surfaces which are correlated to one another.
A lens for high definition purposes is known from East German Pat. No. 140,087, which consists of a hollow mounting cell and of several lenses to be fastened in this mounting cell and fixed in individual mountings. For this purpose, the lenses are made as truncated cones which can be inserted into the likewise truncated-cone-shaped hollow space of the mounting cell. In this way, the cone angles of the individual mountings must correspond to that of the mounting cell, as do also the maximum and minimum diameters. This necessitates extremely close tolerances and high requirements with respect to the product accuracy. Repeated assembly and dismantling, for example, for the purpose of adjustment or selection, is difficult and requires special devices.
A lens mounting support for holding a lens system is known from German Pat. No. 2,061,661. It consists of webs which, at three locations at least of the inner wall of the mounting, are bulged up by the formation of grooves according to a non-cutting metal working process and are then calibrated. The mountings used are in one piece and therefore can be easily worked on, and the webs can be made very simply and accurately with normal tools. This known clearancefree seating is suitable for micro lenses, but in photographic lenses with stepped mountings it leads to technical difficulties in production and would also require accurate adherence to the tolerances in larger sizes.
East German Pat. No. 135,123 describes the configuration of the mounting parts of a multielement lens, wherein the surface quality on the mounting part surfaces correlated with one another is reduced and the fit tolerances on these parts are increased, as a result of which the machining effort is reduced. A frictional connection is made between the individual lens elements having metal mountings and a tube. This is accomplished by providing at least one of the surfaces of the tube and the mountings, which are correlated with one another by frictional connection, with a certain roughness height, whereby the outside diameters of the mountings are larger than the inside diameter of the tube at most by the amount of the roughness height. In this known arrangement, the frictional fixing is effected by lasting deformation of the annular structure having increased roughness height.